LATTICE WORKERS, OR POLYCYSTINA. 93 



opinion, that the whole organism, notwithstanding 

 its variations, is unicellular, and remains through life 

 a true individual cell. 



The outer capsule (extra-capsuluni] includes all 

 those parts of the soft body which lie outside the 

 central capsule. It consists of a gelatinous mantle, 

 which completely surrounds the central capsule, but 

 is separated from its outer surface by a thin layer of 

 protoplasm. The pseudopodia radiate from this 

 thin layer, penetrate the gelatinous mantle, and form 

 a network on its surface, whence they extend into 

 the surrounding water. 



Cienkowski was the first to observe that the 

 " yellow cells," already referred to as supposed 

 " sarcoblasts," live independently after the death of 

 the Radiolaria, and in consequence that they do not 

 belong to it, but are unicellular parasitic algae, to 

 which the name of Xanthella has been given. 



The pseudopodia, or thread-like processes, exhibit 

 the same peculiarities as in all true Rhizopods ; they 

 are usually very numerous, long and thin, flexible 

 and sensitive filaments of sarcode, which exhibit the 

 peculiar phenomena of granular movement. They 

 serve as active organs for the inception of nutriment, 

 for locomotion, sensation, and the formation of the 

 skeleton. 



The skeleton of the Radiolaria, says Haeckel, " is 

 developed in such exceedingly manifold and various 



